(P07-007-23) Human Milk Fatty Acid Composition in Relation to Maternal Diet: Findings From the JiVitA-3 Study

Objectives: Human milk fatty acids (FA) are sensitive to maternal nutrition and n-3 polyunsaturated fatty acids (PUFA) are implicated in immunity and cognition in infants. We assessed human milk FA composition, compared it to infant intake recommendations, and evaluated associations with maternal diet at 3 months postpartum among women of rural Bangladesh.

Methods: In a trial (JiVitA-3) of antenatal multiple micronutrient or iron-folic acid (IFA, standard of care) supplementation, a casual human milk sample and dietary intake as servings of food items consumed in the last week were collected from mothers at 3 months postpartum. Milk lipid content was measured gravimetrically, and FA were analysed by gas chromatography in samples from exclusively breastfeeding women in the IFA group (n=119). Prevalence of adequate amounts of α-linolenic acid (ALA) and docosahexaenoic acid (DHA) in milk were assessed using FAO recommended cut-offs of ≥0.4% and ≥0.2% of total FA, respectively. Associations of specific food intakes with milk FA (as % of total FA) were explored using linear regression analysis.

Results: Milk fat and energy content (mean ± SD) were 34.9 ± 13.1 g/L and 625 ± 113 kcal/L, respectively, with fat contributing ~50% of energy intake. As a percent of total FA, saturated, monounsaturated, and PUFA were 55.0 ± 5.6%, 28.6 ± 5.6%, and 11.0 ± 3.8%, respectively, with palmitic (28.0 ± 3.8%), oleic (23.4 ± 5.4%), myristic (10.7 ± 3.3%), and linoleic (8.6 ± 3.3%) acids predominant. ALA and DHA concentrations in milk met infant intake recommendations in 74% and 92% of cases, respectively, assuming a milk intake of 780 ml/day. Each serving of maternal fresh fish intake (median 3; IQR 1-7) was associated with gains in the % of n-3 PUFA in human milk: ALA β=0.019 (95% CI 0.005, 0.034), DHA, 0.007 (0.004, 0.01), eicosapentaenoic acid, 0.003 (0.001, 0.004), and docosapentaenoic acid, 0.006 (0.0001, 0.012). Milk n-3 PUFA were higher (38% relative increase) in milk from women who consumed >7 servings of fresh fish in the past week.

Conclusions: Concentration of n-3 PUFA in human milk were likely to meet recommended intakes for the majority of infants aged 0-6 months and were responsive to maternal fish intakes in rural Bangladesh, suggesting a locally appropriate dietary modification to improve milk FA composition and benefit infant health in this setting.

Funding Sources: Bill and Melinda Gates Foundation